diff --git a/pg4wp/driver_pgsql.php b/pg4wp/driver_pgsql.php
index fc7e2fe..fbc9834 100644
--- a/pg4wp/driver_pgsql.php
+++ b/pg4wp/driver_pgsql.php
@@ -157,6 +157,9 @@
 			if( false !== strpos( $sql, 'USE INDEX (comment_date_gmt)'))
 				$sql = str_replace( 'USE INDEX (comment_date_gmt)', '', $sql);
 			
+			// HB : timestamp fix for permalinks
+			$sql = str_replace( 'post_date_gmt > 1970', 'post_date_gmt > to_timestamp (\‘1970\')', $sql);
+			
 			// ZdMultiLang support hacks
 			$sql = preg_replace( '/post_type="([^"]+)"/', 'post_type=\'$1\'', $sql);
 			$sql = str_replace( 'link_url o_url', 'link_url AS o_url', $sql);